This invention relates generally to double-acting overrunning clutches. More particularly, it relates to a double-acting overrunning clutch of the sprag type wherein engagement is direction-sensitive in that the clutch may be engaged in either direction of rotation and yet be free to permit relative rotation of the clutch members.
Some conventional sprag type overrunning clutches include spaced clutch race members with sprags interposed therebetween. They include a pair of cages to insure that the sprags move together. The cages are arranged to grip the sprags so as to maintain their position and to provide a biasing force tending to engage the sprags with one of the races. This may create undesirable stresses in the sprag assembly, which could interfere with the speed of its response.
Other conventional sprag type overrunning clutches include sprags which define one engaging surface at each end thereof. The surfaces are generally cylindrical with their centers displaced laterally. This provides for a one-way overrunning operation which is not direction-sensitive.